Patients with irritable bowel syndrome (IBS) have chronic abdominal pain as a result of visceral hypersensitivity. Voltage-gated sodium channels control cellular excitability and are involved in the pathophysiology of several functional gastrointestinal disorders. Researchers from Nocion Therapeutics Inc. and the University of Oklahoma recently reported on the preclinical testing of NTX-1175, a sodium-channel blocker, in rat models of acute colonic hypersensitivity to distension.